Analysis method of weather analysis
On the weather map, analyze the weather system and atmospheric state of a certain area. Including: ① air pressure analysis. Use isobar or contour line to represent the distribution of space air pressure. ② Temperature analysis. The distribution of cold and warm air masses in the atmosphere and the thermodynamic structure of the atmosphere are expressed by isotherms. ③ Humidity analysis. The distribution of water vapor content in the atmosphere is represented by equal specific wet line or equal dew point line. ④ Wind field analysis. The characteristics of atmospheric flow are expressed by streamline and isowind. On the basis of these analyses, air mass analysis, frontal analysis and air pressure system (or wind field system) analysis can be carried out.
diagnostic analysis
Using atmospheric sounding data or processed data (see meteorological data processing), various atmospheric physical quantities are calculated, and the atmospheric circulation and weather system are quantitatively analyzed by atmospheric dynamic equations and physical equations, which is an analysis technology developed from the early 1970s. This analysis method is superior to the qualitative analysis method of weather map. Through diagnosis and analysis, we can further understand the physical mechanism of the occurrence and development of weather system and provide objective physical basis for weather forecast. Commonly used physical quantities include energy, vertical velocity, vorticity, divergence, water vapor transport and so on. For example, energy diagnostic analysis is to calculate various factors that cause energy changes from the energy equation and analyze their maintenance, balance and transformation. Generally speaking, the increase of kinetic energy means the development of the weather system, and the decrease of kinetic energy often makes the weather system tend to decline. The calculation results of mature cyclone system show that kinetic energy is mainly generated in the upper and lower troposphere. Because the low-level airflow obviously flows from high pressure to low pressure through the isobar, it shows that the pressure field does work on the air block and produces kinetic energy. When this kinetic energy is greater than the energy output to the outside of the system and the friction consumption, the cyclone can be maintained and strengthened. Due to the application of high-speed computer, diagnostic analysis has developed from the analysis of historical data to an important technology of daily weather analysis.
Radar data analysis
Using the detection data of weather radar, meteorological Doppler radar, lidar (see laser atmospheric remote sensing) and acoustic radar (see acoustic atmospheric remote sensing), the atmospheric physical state and atmospheric motion within several hundred kilometers are analyzed.
Satellite cloud image data analysis
The distribution of clouds, wind, temperature, pressure and humidity in the global atmosphere is analyzed by using satellite cloud images, satellite wind measurements and satellite radiosondes (see satellite meteorology).
objective analysis
The weather analysis of the period is carried out manually, which is usually called subjective analysis. Using high-speed electronic computer to imitate manual operation to draw weather map and interpolate meteorological elements to grid points as the initial value of numerical forecast is called objective analysis, or computer analysis. However, there are still some shortcomings and deficiencies in the computer analysis scheme and technology, which can not completely replace the analysis and judgment of the human brain. Some weather charts are analyzed by machine first, and then supplemented and corrected manually, which is called man-machine combined analysis. The objective analysis includes not only the live weather map, but also the diagnostic analysis of various physical quantities, radar and satellite image recognition.